Fighting bolt bounce in a M16-with a ceiner kit. Will a bore body weight set help?

[unclebear]

I am looking at the AR-22 adjustable weight set, gen 4.
I really like my old ceiner kit,I have 2 backups so the grandkids can still play...
Also wondering if the bore buddy barrel collar would help.
I now have one of Mak 91's am-180 adaptors and I am chomping at the bit to let it rip.

 

[strobro32]

The perfect bolt weight for any AR22 go fast is the 1.25 oz weight. CMMG only sells the one because it works. It needs to rattle on the kit to counter act the bolt bounce.

 

[KickStand]

I printed a spacer that went in front of the buffer. The spacer compresses the ar15’s buffer spring; therefore, it increases the back pressure on the entire conversion kit (pushing it forward). I then bought a cmmg 22 kit and their auto trip and weight. The rest is history.


Edit: Here’s the aforementioned setup running. I filmed this by myself and the quality ain’t the best but it’ll show you what’s what.

 

[unclebear]

I did not realize the entire kit could move .
So your buffer spacer is like the 4 quarter trip.
Your M-16 is amazing !

 

[KickStand]

I did not realize the entire kit could move .
So your buffer spacer is like the 4 quarter trip.
Your M-16 is amazing !

Thank you and yes, your entire kit can move. I reckon adding four quarters would help; however, I printed something about an .75” or so long.

 

[SecondAmend]

I might have posted this info and some representative ROFs previously here on UziTalk and on ARFCOM, but at the risk of repeating myself:

Over several years I've made more than a dozen .22LR Atchisson/Ciener pattern "anti-bounce weights" (ABWs) for less than two dollars each. Last ones I made were in 2022. All work as well as the commercially sold ones from Ciener (which was what I used as a model) and CMMG (old and new types).

An easy way to get cheap ABWs is to buy a 3/4X1X2 Hillman spacer (H#880425). Split it in half and then grind and file to match the basic Ciener dimensions (the Hillman spacer is a little too long). Cheapest way is to buy some 3/4 in. black pipe (not galvanized) cut to desired length (just under 2 in.) then split, grind and file to fit. These pipe ABWs come in at right around the same 1 oz. of the Atchisson/Ciener ABWs. With the black pipe version, it's easy to add additional weight by fitting and fastening sections of 1/2 in. black pipe inside the 3/4 in. ABW. I've got functioning weights ranging from 0.75 oz. to 1.34 oz. For reference, I've got Atchisson/Ciener (just under 1 oz.), old pattern CMMG (about 0.8 oz.), and new (2023) CMMG (about 1.27 oz.). I typically use a 1 to 1.1 oz. ABW as it provides a relatively low ROF while still working with SV ammo (which doesn't function in my M16 with standard FCG springs and components.

I've never had the need to use any type of plug, spacer, pusher, quarters, or the like between the AR-buffer and the back of the .22LR assemblies (using several .22LR conversions and two dedicated .22LR uppers) with two different M16s. I have some thoughts, but no definite reason why such things seem to be needed by some users.

Best of luck!
MHO, YMMV, etc.

 

[SecondAmend]

The perfect bolt weight for any AR22 go fast is the 1.25 oz weight. CMMG only sells the one because it works. It needs to rattle on the kit to counter act the bolt bounce.

Pre 2023 CMMG .22LR setups had a lighter ABW (own ~2012 purchase IIRC, about 0.75 oz.). My experience has been that with SV ammo, a 4.5 in. barrel, and standard M16 FCG springs and other components, the new pattern CMMG ABW sometimes has less than 100% reliable operation. Could be the magazines I use put too much drag on the bolt, and that combined with the heavier ABW causes the failures to extract/eject properly. Doesn't seem to be an issue with "zippy" ammo.

MHO, YMMV, etc.

 

[strobro32]

I only use CCI MM 40 gr RN.

 

[KickStand]

I use the cheapest stuff and it has all worked for my m16 22 conversion (might have one or two that hasn’t worked but I can’t recall any). I don’t think I’ve ever bought cci mm either (cost 2 much).

 

[amphibian]

I printed a spacer that went in front of the buffer. The spacer compresses the ar15’s buffer spring; therefore, it increases the back pressure on the entire conversion kit (pushing it forward). I then bought a cmmg 22 kit and their auto trip and weight. The rest is history.


Edit: Here’s the aforementioned setup running. I filmed this by myself and the quality ain’t the best but it’ll show you what’s what.

My cheap solution I did like 20+ years ago:

 

[SecondAmend]

Those of us "old timers" might still recall the Spike's Tactical .22LR AR-15/M16 conversion assembly that counteracted bolt bounce by incorporating both a relatively light (~0.7 oz.) anti-bounce weight and a so-called ball-detent (i.e., a spring- loaded ball in the bolt that intersected into notches in the inner right side frame rail).

 

[amphibian]

Those of us "old timers" might still recall the Spike's Tactical .22LR AR-15/M16 conversion assembly that counteracted bolt bounce by incorporating both a relatively light (~0.7 oz.) anti-bounce weight and a so-called ball-detent (i.e., a spring- loaded ball in the bolt that intersected into notches in the inner right side frame rail).

A guy that posted on AR15.com back in the day that I think went by the name 'Swede' or something like that came up with that idea.

My friend that was making the kits for Spike's later incorporated that into those kits.
Picture of this mod below is from my website of when I was selling those kits.

 

[unclebear]

Well, I tried to make a additional anti
bounce weight like Second Amendment mentioned.
Filed and hacked at some 1/2 iron pipe until I got tired.
It fit in the kit, it cycles, but the hammer is hanging up on the additional metal.
Back at it tomorrow!

 

[mak91]

A guy that posted on AR15.com back in the day that I think went by the name 'Swede' or something like that came up with that idea.

My friend that was making the kits for Spike's later incorporated that into those kits.
Picture of this mod below is from my website of when I was selling those kits.

How effective was that spring and ball detent mod ?

 

[K2]

Hi All,
ball detent works great. My kits will run w/o the ABW with the ball detent installed.

BTW, putting the ball in is challenging. I cut a sliver of CC as wide as the rail to keep the ball/spring in place over the bumps. Is there a better method of installing the ball?

Enjoy,

K2

ps. I found the ball detent mod on AR15.com 20+ years ago. My kits were not reliable until I did the mod. My kits also have the timing set late.

 

[SecondAmend]

Well, I tried to make a additional anti
bounce weight like Second Amendment mentioned.
Filed and hacked at some 1/2 iron pipe until I got tired.
It fit in the kit, it cycles, but the hammer is hanging up on the additional metal.
Back at it tomorrow!

Using an Atchisson/Ciener ABW as a guide, it still took me scrapping out my first couple tries to get ones that fit. And even after that on a couple of others as I was making more, I took off too much metal in places with my hacking and filing and had to scrap them.
I hope things work out for you. Sure beats buying ABWs at the prices the commercial market charges, even if you have to scrap a few.
MHO, YMMV, etc.

 

[SecondAmend]

Hi All,
ball detent works great. My kits will run w/o the ABW with the ball detent installed.

BTW, putting the ball in is challenging. I cut a sliver of CC as wide as the rail to keep the ball/spring in place over the bumps. Is there a better method of installing the ball?

Enjoy,

K2

ps. I found the ball detent mod on AR15.com 20+ years ago. My kits were not reliable until I did the mod. My kits also have the timing set late.

I had a Spike's .22LR conversion kit in the 2010 or so time frame. Like so many things firearms related, I found the ball-detent to be firearm configuration and ammo dependent. With the M16 configuration that I had at the time, and any "zippy" ammo, the ball-detent was insufficient to counteract the bolt bounce. At the time, I tried heavier and lighter recoil springs as that was the suggestion prevalent back then, to no avail. As it turned out, the shooting range where I had been shooting at the time became unavailable, so I sold the M16 to one party, and the Spike's kit to another.
Some time later, I was able to find another place to shoot full auto, bought another M16, and now mostly use any of several CMMG .22LR conversions or dedicated uppers, and my self-made AWBs of a weight that works with the configuration and ammo I'm using.
I still have a ball and spring, and could probably drill one or more bolts and notch or more right-side frame rails, but why when it's so easy to just slip cheap ABWs in and out?
Best of luck.
MHO, YMMV, etc.

 

[unclebear]

The sear trip is fairly thin ,I don't think it is a 1/8 " wide .not a lot of metal to play with there .

 

[unclebear]

Success !
The bore buddy weight did the trick and the gun is running great.
Used the heavy weight with 1 loose lead weight that could slide inside the unit .
Did not have to use a spacer in front of the plug .
Now onward to the 165 round drum!

 

[SecondAmend]

The CMMG and Ciener ABWs that I have work just fine, it was just a lot cheaper to make my own ABWs (was two for $1.50, now $1.78, and I've made a dozen or so) when I wanted to avoid having to buy a new one for each .22 upper or conversion. Cutting a 3/4x1x2 spacer in half, cutting two notches in each half, then trimming the halves to size is not rocket surgery.

MHO, YMMV, etc.

As I think about this some more, and I might not be remembering correctly, but weren't the really heavy bolt weights specifically developed for use with .17WRM and .22MAG rimfire semi auto applications?

Atchisson developed his .22RF setup in 1980, and it's been successfully used since then.